Simplified Chinese Version of the Spinal Instability Neoplastic Score in Evaluating Patients with Metastatic Spinal Tumor: A Cross‐Cultural Adaptation and Validation

ObjectiveTo translate the original English version of the Spinal Instability Neoplastic Score (SINS) into simplified Chinese, adapt it cross‐culturally, validate its psychometric properties in measuring spinal instability in patients with metastatic spinal tumors in the Chinese mainland, examine the reliability and validity to demonstrate its accuracy and applicability in clinical practice.MethodsPatients diagnosed with metastatic spinal disease between January 2016 and January 2020 were recruited. The number of participants was advised to be at least 50 for appropriate analysis of reliability, construct validity, as well as ceiling or floor effects, and recruitment of 100 patients was advised for internal consistency analysis. The study was conducted in two phases: first, the SINS was translated into simplified Chinese; second, the factor structure, internal consistency, test–retest reliability, validity, and floor and ceiling effects of the SC‐SINS were assessed. The internationally recognized cross‐cultural adaptation guidelines were followed. Internal consistency was evaluated with Cronbach''s alpha. Test–retest reliability was examined among the patients with a 4‐week interval. The validity of the Chinese version of SINS (SC‐SINS) was assessed by examining its relationship with Kostuik classification. Principal component analysis was conducted to confirm the factor structure of each subscale.ResultsA total of 160 participants (88 males and 72 females) were enrolled. No major difficulties occurred in the forward and backward translations of SINS. The internal consistency of SC‐SINS was excellent (Cronbach''s α =0.857, ranging from 0.68 to 0.85). Test–retest reliability was also excellent with a value of 0.89, ranging from 0.86 to 0.95. Validity analyses indicated that the SC‐SINS was positively and significantly correlated with Kostuik classification. The correlation between “Posterolateral Involvement of Spinal Elements” and “1‐2 Partial Damage” was the highest with a correlation value of 0.792. The correlation between “Pain” and “1–2 Partial Damage” was the lowest with a value of 0.341. All items showed principal component coefficients greater than 0.4. The values of Factor 1 ranged from 0.523 to 0.681; Factor 2 ranged from 0.591 to 0.731; Factor 3 ranged from 0.613 to 0.754; Factor 4 ranged from 0.461 to 0.711; Factor 5 ranged from 0.513 to 0.701; and Factor 6 ranged from 0.501 to 0.668. In addition, neither floor nor ceiling effects were seen in the SC‐SINS.ConclusionThe SC‐SINS demonstrated high internal consistency and test–retest reliability, which has been proven valid and reliable to measure spinal stability in patients from the Chinese mainland with metastatic spinal tumor.     

Role of site-directed mutagenesis and adjuvants in the stability and potency of anthrax protective antigen

Anthrax is a zoonotic infection caused by the gram-positive, aerobic, spore-forming bacterium Bacillus anthracis. Depending on the origin of the infection, serious health problems or mortality is possible. The virulence of B. anthracis is reliant on three pathogenic factors, which are secreted upon infection: protective antigen (PA), lethal factor (LF), and edema factor (EF). Systemic illness results from LF and EF entering cells through the formation of a complex with the heptameric form of PA, bound to the membrane of infected cells through its receptor. The currently available anthrax vaccines have multiple drawbacks, and recombinant PA is considered a promising second-generation vaccine candidate. However, the inherent chemical instability of PA through Asn deamidation at multiple sites prevents its use after long-term storage owing to loss of potency. Moreover, there is a distinct possibility of B. anthracis being used as a bioweapon; thus, the developed vaccine should remain efficacious and stable over the long-term. Second-generation anthrax vaccines with appropriate adjuvant formulations for enhanced immunogenicity and safety are desired. In this article, using protein engineering approaches, we have reviewed the stabilization of anthrax vaccine candidates that are currently licensed or under preclinical and clinical trials. We have also proposed a formulation to enhance recombinant PA vaccine potency via adjuvant formulation.     

YouTube provides insufficient information on patellofemoral instability

Objective:Videos uploaded to YouTube do not go through a review process, and therefore, videos related to patellofemoral instability may have little educational value. The purpose of this study was to assess the educational quality of YouTube videos regarding patellofemoral instability.Methods:A standard search was performed on the YouTube database using the following terms: “unstable kneecap,” “patellar instability,” “patellofemoral instability,” “kneecap dislocation,” and “patellar dislocation,” and the top 50 videos based on the “relevance” assignment of the YouTube algorithm were included for analysis. The properties, content, and source of each video were recorded. The educational quality of videos was analyzed according to scores obtained using DISCERN, the criteria of Journal of the American Medical Association, Global Quality Score, and Patellofemoral Instability Specific Score, and the quality of the videos was evaluated according to the groupings of these scoring systems.Results:A total of 250 videos were identified, of which 89 were included in the study for analysis. The mean video duration was 11.72 ± 22.03 minutes. The median number of views was 4516.5 (range, 3-6 044 971). The content of the videos was disease-specific in 60%, 20% were related to surgical technique or approach, and 14.1% were exercise videos. Most of the videos were uploaded by physicians (33.7%). The Global Quality Score and DISCERN scores were significantly correlated with video duration. The Patellofemoral Instability Specific Score was significantly correlated with video duration, number of views, view rate, likes, and Video Power Index. According to the DISCERN classification, 69.9% of the videos were very insufficient or insufficient. According to the Patellofemoral Instability Specific Score, 65.2% of videos were evaluated as very low or low. According to the Global Quality Score, 60.7% of videos were rated as poor quality.Conclusion:The quality of YouTube videos about Patellofemoral instability is insufficient. It was found that viewers tend to watch short and low-quality videos.     

Instability After All-Cause Acetabular-Only Revision Total Hip Arthroplasty Remains a Clinical Problem

BackgroundThe purpose of this study is to (1) evaluate the rate of instability and reoperation after acetabular component–only revision, (2) compare instability rates across various head sizes, and (3) determine patient factors correlating with postoperative instability.MethodsWe retrospectively reviewed all isolated acetabular component revisions (n = 200) at our institution between 2007 and 2017. Patients with less than one-year follow-up were excluded. Patients were subdivided into 4 head size groups: (1) 32 mm or less, (2) 36 mm or more, (3) dual mobility, and (4) constrained liners. Factors including the body mass index, cup position, prior revision(s), and subsequent reoperation were compared across groups.Results189 patients (200 hips) met the inclusion criteria. The overall rate of instability was 12% (n = 24), and 37 (18.5%) cases underwent subsequent revision, including 11 cases for recurrent instability. There was no significant difference in postoperative dislocation or reoperation for instability across the various groups. The use of a constrained liner trended toward the highest rate of postoperative instability (36.4%, P = .090). History of preoperative instability was a significant risk factor for postoperative instability with or without history of prior revision (P = .011 and P = .001, respectively).ConclusionContemporary isolated acetabular revision is still associated with significant rates of instability. Surprisingly, the head size was not a predictive factor for postoperative dislocation or reoperation, but a prior history of instability was associated with postoperative instability. Patients revised to a constrained liner experienced highest rates of failure and remain an unsolved clinical problem.     

Outcome of anterior cruciate ligament reconstruction in children and adolescents: A retrospective study

BackgroundIndications and outcomes of anterior cruciate ligament (ACL) reconstruction in children and adolescents is still controversial. It was the aim of this study to analyze outcomes of anterior cruciate ligament reconstruction in this special age group.MethodsRetrospectively, we analyzed 62 consecutive cases of ACL reconstruction using a physis crossing technique in six to 16-year-old patients with a mean follow-up of 69 months.ResultsCases operated later than six weeks after trauma had significantly more meniscal lesions than patients operated within six weeks of trauma. At last follow-up, we found good or very good subjective and objective results in 71% of the patients.ConclusionIn active and healthy children with anterior knee instability after ACL tear, ligament reconstruction is a safe and successful procedure and should be considered within six weeks of trauma because instability seems to promote secondary meniscal lesions.